Apparatus for dry-cleaning and degreasing of fibrous material



Sept. 18, 1951 T. HOFFMAN APPARATUS FOR DRY CLEANING AND DEGREASING OFFIBROUS MATERIAL Filed Feb. 4, 1947 2 Sheets-Sheet 1 INVENTOR.

P 1951 M. T. HOFFMAN 2,567,938

APPARATUS FOR DRY CLEANING AND DEGREASING OF FIBROUS MATERIAL Filed Feb.4, 1947 I 2 Sheets-Sheet 2 IN V EN TOR.

Patented Sept. 18, 1951 UNITED STATES PATENT OFFICE APPARATUS FORDRY-CLEANING AND DE- GREASING F FIBROUS MATERIAL Manfred T; Hoffman,Newburyport, Mass.

Application February 4, 1947, Serial No. 726,428

3 Claims.

This is a continuation in part of my copending application Ser. No.548,620, filed August 8, 1944, for Apparatus for Dry Cleaning, nowPatent 2,479,358. v

The present invention relates to apparatus for dry cleaning anddegreasing of fibrous material. The term fibrous material is intended toinclude wool, hair, furs and skins and any other materials of animalorigin which consist of animal fibers, or comprise such fibers.

One object of the present invention is to provide a novel apparatus fordry cleaning of fibrous materials in a continuous operation asdistinguished from the batch method in which limited quantities ofmaterial are immersed and treated in successive operations in a bath ofdry cleaning agent.

Another object of the present invention is to provide means for drycleaning the fibrous material which are, inessence, automatic, thusminimizing the requirement of hand laborand being easier to control thanthe means which were used heretofore for dry cleaning of fibrousmaterial.

Still another object of the invention is to provide a novel apparatusfor dry cleaning of fibrous materials which is effective forsimultaneously removing impurities and foreign matter such as, forinstance, grease, paint, pitch or tar.

Still another object of the present invention is to provide apparatusfor dry cleaning fibers in 'a continuous operation which requires lessfioor space and is easier to manufacture than the type of apparatuswhich is shown in my Patent 2,479,358.

Other objects of the present invention will become apparent as thisdescription proceeds.

In the apparatus of the present invention the material to be dry cleanedand degreased is moved in a wet state through a cleaning zone and, whilebeing moved through said zone, subjected to a rubbing action having thesame direction as the direction of the movement of the material throughsaid cleaning zone. Any suitable dry cleaning agent or mixtures thereofmay be used for wetting the material to be dry cleaned as, for instance,trichlorethylene, carbon tetrachloride or tetrachlorethylene. The fibersto be treated may be in the form of an eiognated layer which may consistof uncarded, unwoven fibers as, for instance, raw wool. bing actionwhich has the same direction as the direction of movement of thematerial through the cleaning zone may be achieved by a pair ofrotatable rolls adapted to engage opposite sur faces of a layer offibrous material and being positively rotated at unequal surface speeds.

The invention will be better referring to thefollowing specification andto the appended drawings, wherein:

Fig. 1 is a side elevation of, and partly a vertical The abovereferred-to rubunderstood by 2 section through, a preferred embodimentof a dry cleaning apparatus;

Fig. 2 is a section along line 22 of Fig. 1 showing a front view ofcleaning rolls of the apparatus shown in Fig. 1 and also showing otherparts which are associated with said rolls;

Fig.3 is a side elevation of, and partly a vertical section through, amodification of the apparatus which is shown in Fig. l and Fig. 4 is adiagrammatic side elevation of still another apparatus for dry cleaningfibrous material.

The same reference signs have been used in all figures to designate likeparts.

The apparatus which is shown in the drawing is intended to be used incombination with a system for continuously and automatically purifyingthe dry cleaning agent and recirculating the same. That system has beenfully described in my above referred-to Patent'2,479,358 and has,therefore, been omitted from the present drawings.

Referring now to Fig. l of the accompanying drawing, the cleaningapparatus has generally been indicated by the reference sign I. Cleaningapparatus l is aranged in a substantially gastight chamber 2. Cleaningagent is supplied to the top of the cleaning chamber 2 by a system ofpipes or spray nozzles 3. The cleaning agent, upon having passed throughchamber 2, is collected in a funnel-shaped basin 4 forming the bottom ofchamber 2. Apron 5 feeds the top portion of chamber 2 continuously withfibrous material 6 to be cleaned, for instance, raw wool. The jets l ofdry cleaning agent coming from nozzles 3 are aimed at the fibrousmaterial as it leaves apron 5 and drops between the nip formed between apair of rotatable rollsB and 9. The shaft l8 of roll 8 is driven bymotor II by means of a belt l2 and. pulley l3 arranged on shaft [6. Spurgear I i on shaft Id meshes with spur gear IE on shaft [6 of roll 9. Thediameters of rolls 8 and 9 may be equal, but the diameters of spur gearsI4 and I5 are so selected that rolls 8 and 9 are rotated at differentsurface speeds. By reason of this difference in surface speed thefibrous material is subjected, while being moved through a cleaningzone, to a rubbing action which has the same direction as the directionof movement of the material through said zone.

In my above referred-to Patent 2,479,358 I have mainly described meansfor subjecting the material to be dry cleaned to a rubbing action in adirection transversal of the direction of movement of the materialthrough a cleaning zone. I have found, however, that in certain cases itis preferable to effect, and easier to achieve, a rubbing action in thedirection of the movement of the material through the cleaning zone.

As may best be seen from Fig. 2 shaft l0 rests in bearings I! which areacted upon by helical springs 18. The amount of pressure whlch springsl8 exert upon bearings i! and consequently upon the roll 8 may beadjusted by means of screw-threaded bolts 19 held in position by nuts20. The amount of pressure which should preferably be exerted by thesprings l8 depends upon the material which is to be treated as well asupon the nature and the amount of impurities which are containedtherein, and for this reason provision has been made of means forvarying the amount of pressure by which cooperating pairs of rolls 8, 9are pressed against each other. The surfaces of cooperating pairs ofrolls 8, 9 are smooth and highly polished and the pressure which tendsto keep them in linear engagement is preferably high. Wool to be drycleaned and degreased is not harmed even if the pressure of springs I8or of weights which are used in their place is very high.

Paint, grease and other impurities which have not been completelydissolved by the dry cleaning agent will have a tendency to adhere tothe surfaces of the rolls 8 and 9, from where such substances may beremoved by means of scraper blades 2|. These scrapers have been shown inFig. 1 in a more or less diagrammatic way and I prefer that particularscraper design which has been shown in my Patent 2,479,358. If thescraper blades are arranged as shown in Fig. 1, it may be necessary ordesirable to arrange a tray (not shown in the drawing) below of eachscraper blade in order to prevent impurities dropping from the scraperblades to soil the fibers which were previously cleaned.

In addition to rolls 8 and 9 chamber 2 houses a cooperating pair ofrolls 22 and 23 and a cooperating pair of bottom rolls 24 and 25. Spurgear 15 engages a small gear 26 which, in turn, engages spur gear 21 onshaft 28 of roll 23. Spur gear 29, which is likewise mounted on shaft28, engages spur gear 38 which is mounted on shaft 3| of roll 22. Spurgear 21 meshes with a small gear 32 which, in turn, meshes with spurgear 33 which is mounted on the shaft 34 of roll 25. Spur gear 33engages spur gear 35 which is mounted on the shaft 36 of roll 24. Thusall pairs of cooperating rolls 8, 9; 22, 23 and 24, 25 are operatedpositively by means of a common motor II. The left bank of rolls 9, 23and 25 is carried by shafts the bearings of which are rigidly mounted ina frame structure 52 or form part of such a structure, while the rightbank of rolls 8, 22 and 24 is supported by shafts the bearings of whichare movable relative to the frame structure 62 and are acted upon byseparate springs 18, thus making it possible for each shaft of the rightbank of rolls to move relative to the other shafts of said bank ofrolls. It will be noted that the entire transmission system foroperating rolls 8, 9; 22, 23 and 24, 25 is located outside of thechamber 2 wherein said rolls are housed. The ratios between thedifferent spur gears which form the transmission system is selected insuch a way that rolls 22 and 23, and 24 and 25, respectively, arerotated at different surface speeds, thus subjecting the material whilebeing moved through the bites formed between these two pairs of rolls toa rubbing action having the same direction as the direction of movementof the material. The ratio of the different spur gears which form thetransmission system is selected in such a way that pairs of cooperatingrolls 22, 23, and 24, 25, respectively, which are situated more remotelyfrom the feed end rolls 8, 9, are ro- '4 tated at relatively highersurface speeds. Thus, the surface speeds of rolls 22 and 23 are higherthan the surface speeds of rolls 8 and 9 and, in turn, the surfacespeeds of rolls 24 and 25 are higher than the surface speeds of rolls 22and 23. By reason of the aforementioned grading of the surface speeds ofpairs of cooperating rolls the capacity of conveying fibrous material isincreased from the feed end of the machine toward its delivery end, thusprecluding plugging of the machine by lumps of fibers which may dropdown from a pair of cooperating rolls located on a higher level to apair of cooperating rolls located on a lower level. The aforementionedgrading of the surface speeds of cooperating pairs of rolls results inthat a drawing action in the direction of its travel through the machineis being exerted upon fibrous material which is in the form of a more orless coherent layer. Such drawing action tends to facilitate the removalof foreign matter from relatively coherent fibrous layers. The lowermostpair of cooperating rolls 24, 25 delivers the cleaned fibers upon aperforated conveyor belt 37 which permits dry cleaning fluid to dropinto funnel shaped basin 4 forming the bottom of chamber 2, from whereit is removed through drain pipe 38. The cleaning fluid escaping throughdrain pipe 38 is transferred to a purification apparatus (not shown),and then recirculated, i. e. reintroduced into chamber 2 by means of thesystem of spray nozzles 3. Fumes of the dry cleaning agent which rise tothe top of chamber 2 are collected by means of a system of pipesindicated at 39 and liquefied in a condenser (not shown), whereupon thedry cleaning agent may be reused in the process of cleaning fibrousmaterial. The fibrous material, before issuing from chamber 2, is causedto pass through a pair of squeeze rolls 40, 4| for extracting excess drycleaning fluid which is removed through funnel shaped basin 4 and drainpipe 38. Squeeze rolls 49, 4| are rotated to advance the cleaned fibrousmaterial out of chamber 2 and are constructed and arranged to form apart of a substantially gastight seal of that chamber.

The apparatus shown in Fig. 1 includes a chamber 42 for effecting, bythe action of heat, a more complete extraction, 1. e. evaporation, ofdry cleaning fluid than is possible by the mechanical action of squeezerolls. Chamber 42 is provided both at its feed end and its delivery endwith substantially gastight arrangements of squeeze rolls of which onlythe squeeze rolls 43 and 44, located at the feed end of chamber 42. areshown in the drawing. Within chamber 42 there extends an endless apron45 adapted to convey fibrous material through said chamber. Below apron45 are located heating devices 46 which cause evaporation of drycleaning fiuid still contained in the cleaned fibers. Solvent expelledfrom the fibers through the action of heat may be collected in acondenser (not shown) and, upon its liquefication, be reused in the drycleaning process. After the fibers are cleaned they may be subjected tocarbonizing, and ought to be subjected to crushing and dustingoperations to remove unsoluble foreign matter, such as burrs and shives,excrements, sand, dust, etc. which still may have remained therein.

In certain cases it may be desirable to heat the working rolls 8, 9; 22,23 and 24, 25, and this can best be achieved by steam or by hot air. Asshown in Fig. 2, the shaft ID of roll 8 and the sha t '6 o ro 9 ay e hllow for the pu p 7' rolls 55 is engageable with the upper, and thelower bankv of rolls 55 is engageable with the lower,surface of thelayer of fibers issuing from conveyerSl. The rolls of said two banks ofrolls are out of registry so as to cause alternate fiexings of any layerof .fibers which is being passed therebetween. Rolls 55 are providedwith a shifting device for oscillating the rolls of one bank of rollsrelative to the rolls of the other bank of rolls to exert transverserubbing pressure by the rolls on the fibrous layer in oppositedirections. A suitable shifting device for such an arrangement ofcleaning rolls has been more fully described in my Patent 2,479,358. Thewetting device 51 which is fed from tank 58 comprises a plurality ofspray nozzles which are adapted to apply clean dry cleaning fiuid to thelayer of fibers at the gaps formed between consecutive rolls of theupper bank of rolls to flush out any dirt left after the dry cleaningbetween the vertical rolls. Cleaning fluid which drops to the bottom ofchamber 56 is removed by a drain pipe 59. Rolls 60 and Si form part of asubstantially gastight seal of chamber 56 permitting the continuousremoval of cleaned fibers.

If desired, cleaning rolls 55 may be arranged in registry rather thanout of registry, as shown on the drawing. Moreover, cooperating pairs ofrolls 55 may be positively operated at different surface speeds insteadof being oscillated in a transversal direction, thus substitutinglongitudiv nal rubbing pressure for transversal rubbing pressure.

It will be seen from the foregoing that the apparatus which is shown inFig. 4 comprises means for advancing a layer of fibers consecutivelythrough two cleaning zones in one of which the layer is precleaned andsubjected to a rubbing action having the same direction as the directionof the movement of the layer, while in the other cleaning zone the layeris subjected to a finishing cleaning action which may include a rubbingaction transversely to the direction in which it is being advanced. Thischange of the direction of the rubbing action in different cleaningzones is conducive to a more complete removal of impurities from thefibers though it is only needed in cases where the fibers are extremelysoiled or dirty. During the finishing cleaning action fresh dry cleaningfluid flushes off any residues of impurities which may have stilladhered to the fibers prior to their passage through extension chamber56.

Referring again to Fig. l, owing to the action of springs 18 pairs ofcooperating rolls 8, 9; 22, 23; 24, 25 may separate to a certain extentwhen pressed apart by fibrous material which is being passedtherebetween. For this reason it is necessary to provide the apparatuswith a special kind of gears, well known in the art, which do not getout of mesh on the occurrence of displacements of the rolls 8, 9; 22, 23and 24, 25 as caused by the passage of fibrous materials of uneventhickness therebetween.

The number of worker rolls 8, 9; 22, 23; 24, 25 which it is desirable toprovide depends upon several factors such as, for instance, the kind ofmaterial which it is desired to process, the nature and the amount offoreign matter contained therein which is sought to be removedtherefrom, and the speed at which the processing is to be effected.

While Fig. 1 shows a layer 6 of loose fibers on the conveyer belt 5, thesame machine may also be used to treat one or more thicknesses offabric, or furs, or skins, or hat bodies upon being hardened or partlyfulled, or any other fibrous matter adapted to be dry cleaned.

It will be understood that by illustrating herein preferred forms ofapparatus for practicing the process of the invention, I do not intendto limit my invention thereto. While I have described and illustratedherein only preferred embodiments of the several mechanisms of theinvention, these may take other form than as specifically shown anddescribed herein. It will be apparent to those skilled in the art thatvarious changes and modifications may be made without departing from thespirit of the invention or from the scope of the appended claims.

It is claimed and desired to secure by Letters Patent:

1. An apparatus for cleaning fibrous material with a dry cleaning agentcomprising two banks of spaced rotatable rolls having smooth and highlypolished surfaces, the rolls forming one bank being adapted to engagecooperatively the rolls forming the other bank, a plurality of pairs ofsaid cooperatively engaging rolls being arranged at different levels,said cooperatively engaging rolls being adapted to engage oppositesurfaces of a layer of fibrous material and to advance the layer throughthe nips formed between cooperatively engaging rolls, each pair ofcooperatively engaging rolls arranged at a relatively higher level beingadapted to feed said layer directly into the nip formed between a pairof cooperatively engaging rolls arranged immediately below, a feedingdevice adapted to feed fibrous material to the nip formed between a pairof cooperatively engaging rolls arranged above the level of at least oneother pair of cooperatively engaging rolls, a wetting device adapted tosupply cleaning agent to the fibrous material prior to its passagethrough said nip, and operating means for the rolls of both bankscomprising gear means for positively rotating each of the rollsconstituting a pair of cooperatively engaging rolls at unequal surfacespeeds for exerting a rubbing action upon the layer of fibrous materialarranged therebetween.

2. An apparatus for cleaning fibrous material with a dry cleaning agentcomprising two banks of spaced rotatable rolls having smooth and highlypolished surfaces, the rolls forming one bank being adapted to engagecooperatively the rolls forming the other bank, a plurality of pairs ofsaid cooperatively engaging rolls being arranged at different levels,said cooperatively engaging rolls being adapted to engage oppositesurfaces of a layer of fibrous material and to advance the layer throughthe nips formed between cooperatively engaging rolls, each pair ofcooperatively engaging rolls arranged at a relatively higher level beingadapted to feed said layer directly into the nip formed between a pairof cooperatively engaging rolls arranged immediately below, a feedingdevice adapted to feed fibrous material to the nip formed between a pairof cooperatively engaging rolls arranged above the level of at least oneother pair of cooperatively engaging rolls, a wetting device adapted tosupply cleaning agent to the fibrous material prior to its passagethrough said nip, and operating means for the rolls of both bankscomprising gear means for positively rotating each of the rollsconstituting a pair of cooperatively engaging rolls at unequal surfacespeeds for exerting a rubbing action upon the layer of fibrous materialarranged therebetween, said operating means including gear means forrotating at least'one pair of cooperatively engaging rolls situated at arelatively low level at relatively higher surface speeds than one pairof cooperatively engaging rolls situated at a relatively higher level.

3. An apparatus for dry cleaning fibrous material with a dry cleaningagent comprising two banks of spaced rotatable rolls having smooth andhighly polished surfaces, the rolls forming one bank being adapted toengage cooperatively the rolls forming the other bank, the rolls of eachbank being arranged in registry one above the other in a verticaldirection and adapted to engage opposite surfaces of a layer of fibrousmaterial and to advance said layer through the nips formed between pairsof cooperating rolls, each said pairs of cooperating rolls situatedabove the lowest of said pairs of cooperating rolls being adapted tofeed said layer of fibrous material directly into the nip formed betweenone of said pairs of cooperating rolls situated immediately below, afeeding device adapted to feed fibrous material to the nip formedbetween the top pair of said pairs of cooperating rolls, a wettingdevice adapted to supply cleaning agent to the fibrous material prior toits passage through saidnip, and common operating means for the rolls ofboth said banks including gear means for positively rotating each of therolls constituting one of said pairs of cooperating rolls at unequalsurface speeds for exerting a rubbing action upon the layer of fibrousmaterial arranged therebetween.

MANFRED T. HOFFMAN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 4,164 Hoskins Aug. 26, 1845198,557 Bachelder Dec. 25-, 1877 266,248 Worrall Oct. 17, 1882 599,070Turner Feb. 15, 1898 796,530 Quackenbos Aug. 8, 1905 851,539 Malard Apr.23, 1907 899,440 Shuman Sept. 22, 1908 969,952 Harris sept. 13, 19101,400,159 I-Iawley Dec. 13, 1921 1,432,318 Brandwood et a1. Oct. 17,1922 1,527,369 Meyer Feb. 24, 1925 1,626,439 Voegeli Apr. 26, 19271,764,809 Smith June 17, 1930 1,788,840 Mantius Jan. 13, 1931 1,790,392Skelton Jan. 27, 1931 2,025,768 Nieman Dec. 31, 1935 2,223,858Schellenberg Dec. 3, 1940 2,223,860 Schellenberg Dec. 3, 1940 2,284,503Williams May 26, 1942 2,368,916 Drum Feb. 6, 1945 2,479,358 Hoffman Aug.16, 1949

1. AN APPARATUS FOR CLEANING FIBROUS MATERIAL WITH A DRY CLEANING AGENTCOMPRISING TWO BANKS OF SPACED ROTATABLE ROLLS HAVING SMOOTH AND HIGHLYPOLISHED SURFACES, THE ROLLS FORMING ONE BANK BEING ADAPTED TO ENGAGECOOPERATIVELY THE ROLLS FORMING THE OTHER BANK, A PLURALITY OF PAIRS OFSAID COOPERATIVELY ENGAGING ROLLS BEING ARRANGED AT DIFFERENT LEVELS,SAID COOPERATIVELY ENGAGING ROLLS BEING ADAPTED TO ENGAGE OPPOSITESURFACES OF A LAYER OF FIBROUS MATERIAL AND TO ADVANCE THE LAYER THROUGHTHE NIPS FORMED BETWEEN COOPERATIVELY ENGAGING ROLLS, EACH PAIR OFCOOPERATIVELY ENGAGING ROLLS ARRANGED AT AN RELATIVELY HIGHER LEVEL BENGADAPTED TO FEED SAID LAYER DIRECTLY INTO THE NIP FORMED BETWEEN A PAIROF COOPERATIVELY ENGAGING ROLLS ARRANGED IMMEDIATELY BELOW, A FEEDINGDEVICE ADAPTED TO FEED FIBEROUS MATERIAL TO THE NIP FORMED BETWEEN APAIR OF COOPERATIVELY ENGAGING ROLLS ARRANGED ABOVE THE LEVEL OF ATLEAST ONE OTHER PAIR OF COOPERATIVELY ENGAGING ROLLS, A WETTING DEVICEADAPTED TO SUPPLY CLEANING AGENT TO THE FIBROUS MATERIAL PRIOR TO ITSPASSAGE THROUGH SAID NIP, AND OPERATING MEANS FOR THE ROOLS OF BOTHBANKS COMPRISEING GEAR MEANS FOR POSITIVELY ROTATING EACH OF THE ROLLSCONSTITUTING A PAIR OF COOPERATIVELY ENGAGING ROLLS AT UNEQUAL SURFACESPEEDS FOR EXERTING A RUBBING ACTION UPON THE LAYER OF FIBROUS MATERIALARRANGED THEREBETWEEN.